Is this single or Dual 6500 ( VSS or standalone) ?
is the end device have dual connectivity ? or they L2 ?
here is high level steps :
1. Configure New 6807XL - with new IP address for Manangment
2. Connect the New 6807XL with OLD 6500 - port-channel
3. end device have dual connectivity L3 with OSPF - then move 2 leg at a time to Old to New
4. once all device migrated.
5. Move the L3 SVI shut and no shut on new Devices
6. once all Migrated
7. Isolate OLD core from new CORE by shutdown teh port-channel and see any issus reported.
8. any spanning tree configuraion make it as per the requirement become a root bridge.
once i have other information we can make and tweak based on the current setup.
update on new Device stable IOS so it will not required another downtime for upgrade.
if you upgrading from 12.X core to 15.x you need to work on QOS.
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Prerequisites for OSPFv2 Loop-Free Alternate Fast Reroute
Open Shortest Path First (OSPF) supports IP FRR only on platforms that support this feature in the forwarding plane. See the Cisco Feature Navigator, http://www.cisco.com/go/cfn , for information on platform support.
Dont have ISR in hand for testing, what is the version of code running on this ISR ?
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here is the referene guide :
https://community.cisco.com/t5/networking-documents/how-to-configure-pbr/ta-p/3122774
good example :
https://www.networkstraining.com/cisco-asa-policy-based-routing-pbr/
make sure you have verion 9.4.x above.
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i would like to compare, when you manually putting the file name copied versus automatic copy.
suggest to look at the config :
https://sourceforge.net/p/tftp-server/discussion/550565/thread/d737fc9f/
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As long you allowing right traffic and right NAT translation inside to outside and outside to inside.
rest will be blocked. but we are not sure how your setup and configuration, i have provided input based on the screen shot
you need more granular look you need to provide correct information of the IP and your configuration for validation.
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